"I live in a very small, very old house (1919) and everything seemsto creak & squeak. Loudly. The stairs, the floors, and if ceilings
could creak, these would. From the upstairs, you can hear normal levels
of talking downstairs - clearly.

My almost 5 month old son is a
fairly sensitive sleeper. I say sensitive and not light because
sometimes he'll sleep through unimaginable noise in our house; and
other times, he'll wake up when the floor creaks outside his door. If
he wakes out of sound sleep, it's a little messy trying to fall back
asleep. I don't know if it is my fault for having walked on egg
shells during these early months, but I can't somehow bring myself to
whip out the Dyson and "get him used to it" now.

My question
is this: when (God willing) baby #2 comes around, will John be able to
sleep through the constant night wakings and crying of the baby? I'm
not quite sure why, but it really has me nervous. Then I realize lots
of people have multiple children in small homes/apartments- which still
only leaves me half satisfied. Do you have any suggestions & advice
on this topic?"

John sounds like the stereotypical New York City baby (and all you other urban parents will recognize this)--he can sleep through fire engines roaring by outside, but crack the door to make sure he's OK and he wakes up instantly. (That seemed like such a high-larious joke when our kids were 4 months old and the whole mothers' group was so sleep-deprived...)

The short answer to this is: Yes, he will be able to sleep through. Eventually.

The medium answer is: Yes, he will be able to, but it's good you're not having that second baby right now. At almost-5 months almost no babies are heavy sleepers. It's still firmly in the Red Zone of sleep: Will he sleep through the night, or are you still in 4-month-regression hell with a few wake-ups left to go tonight? Will he actually take a nap of more than 20 minutes, or is today just not that day? At this age sleep is still pretty much a crapshoot, so what he does now certainly does not indicate future performance. And honestly, it's got nothing to do with how you treated him in the early days.

The long answer is: People all over the world sleep closer than we in the west do, and would find walls (no matter how thin) a strange luxury. But their kids all adjust to the noise levels and learn to sleep through and around and past each other.

I don't know if you have pets, but if you do, you may have had the experience of having one wake you in the night, but you fall back asleep immediately. Most siblings sleeping where they can hear each other tend to develop that skill, too.

If you can, you'll probably have fewer hassles with sleep if you can avoid having baby #2 right in the middle of a sleep regression for John (9 months, 13 months, 18 months, 25-27-ish months). But even in three months from now he'll be such a radically different sleeper that you probably won't even remember what it was like this week. And he'll adjust to the new baby, although it probably won't be seamless, but you'll work it out.

So my biggest tip is: Wait it out. And try not to have another baby in the middle of the 18-month sleep regression (it's a doozy).

Does anyone out there remember how your kid slept at 5 months? Does it resemble in any way how sensitively they sleep now? How rough was the sleeping adjustment when a new baby came, and how old was the first one when the second arrived?

The Fine PrintMy expertise is in helping people be who they want to be, with a specialty in how being a parent fits into everything else. I like people. I like parents. I think you're doing a fantastic job. The nitty-gritty of what you do with your kids is up to you, although I'm happy to post questions here to get data points of how you could try approaching different stages, because, let's face it, this shit is hard. As for me, I have two kids who sleep through the night and can tie their own shoes. I've been a married SAHM, a married freelance WAHM, a divorcing WOHM, a divorced WOHM, and now a WAHM again. I'm not buying the Mommy Wars and I'll come sit next to you no matter how you're feeding your kid. When in doubt, follow the money trail. And don't believe the hype.